As best I can tell, before calculating the leadfields for the forward model,
the sensor positions are adjusted by the center of the spherical head
approximation as such:
lines 201-205 in compute_leadfield.m
if isfield(vol, 'o')
% shift dipole and magnetometers to origin of sphere
pos = pos - repmat(vol.o, Ndipoles, 1);
pnt = pnt - repmat(vol.o, size(pnt,1), 1);
end
However, I can't find where the modification occurs to vol.o (the sphere's
origin determined in read_ctf_hdm.m) to take into account aligning the
fiducials for the spherical head model to the head coil positions during the
scan. Does anyone know where this calculation is performed?
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